The Area of Land That Drains Into a River System Is

The Area of Land That Drains Into a River System Is

Watersheds Homework
Due Thursday, April 17 / Name ______
Period ______


The area of land that drains into a river system is

known as a watershed. High points in elevation,

ridges and hills, form watershed boundaries by

separating the flow of water into two or more

watersheds. For example: water that falls on top

of a hill may flow down either side of the hill. Water

that flows down one side of a hill will most likely

enter into one watershed while water flowing down

the opposite side of a hill will most likely enter into

a different watershed. The entire areas of land

including mountain tops, hillsides, and valleys

that drain into the river is called a watershed.

Only 1% of the Earth’s water is fresh water available for humans. This makes watersheds extremely important. They collect rainfall, melted snow, sleet, and hail, funneling it back to the larger bodies of water, such as rivers and streams, lakes and ponds, swamps and oceans, and underground sources of water, like aquifers.

Keeping a watershed healthy is an absolute must to provide clean drinking water

and pollutant free lakes, rivers, oceans, and aquifers. Unfortunately, human

activity can contaminate water in numerous ways.

Part 2: Point and Non-Point Water Pollution

There are two types of human water pollution: point source and non-point source.

Point source pollution happens when chemicals or other contaminants from a single, identifiable source enter a body of water. The source of this type of pollution is obvious and can be identified quickly. Point source pollutants are often caused by businesses and industries that use hazardous materials in manufacturing a product. Farms with animal waste storage facilities, pesticides, and fertilizers can also be a source of this type of pollution. The most common point source pollution of groundwater is caused by solvents, paint, and oil products. In addition to oil and fuel pollutants, surface water is also often contaminated by bacteria, viruses, fertilizers, and detergents from sites that do not carefully control their storage or disposal activities.

The second type of water pollution is called non-point source pollution. Non-point source pollution occurs as water moves across the watershed, picking up natural and human made pollutants, on its way to surface streams or groundwater. You or someone you know may be contributing to non-point source water pollution and not even be aware of it. Have you ever washed a car, fertilized your yard, or owned a dog or cat? If you answered yes to any of these questions, you could possibly be causing

pollution. Soap suds from a car can "ow down the street and into a storm drain. The storm drain eventually leads to a steam or river. Soap suds can be deadly to fish and other aquatic creatures. Do you have a nice, green yard? Lawn fertilizer can be washed into a storm drain just like the soap suds. Perhaps you own a pet. Walking Fido down the street to take care of his business can cause pollution . Be sure to carry one of those doggie waste bags to properly dispose of your pet’s waste. Animal waste has harmful bacteria in it.